Mechanical Weathering

There are many types of mechanical weathering. There is release of pressure, freezing and thawing, animal actions, plant growth, and abrasion. While all the types differ greatly, they are all mechanical weathering. Mechanical weathering is the physical breaking down and weathering of rocks by forces of nature.

Freezing and Thawing

Freezing and thawing is one of the three types of mechanical weathering we will be presenting. This particular type occurs when water finds its way into preexisting cracks in rock. Then the water freezes, expanding as it does so. This causes the crack in the rock to widen, and also may even eventually split the rock. This process earned itself the name of “ice wedging” thanks to this. This type of weathering is known to cause and widen cracks in sidewalks and potholes in streets.

This rock was split by ice wedging.

Abrasion

Abrasion is another type of mechanical weathering, and our second example. Abrasion is the process of when sand and other rock particles, such as sediment, are carried by wind, water, or ice over an exposed rock surface. This causes friction, and wears away the rock that it is acting upon like sandpaper on wood.

This rock has undergone abrasion from the pond water's sediments for a while.

Animal Actions

Animals can also cause weathering. Animal actions are yet another type of weathering, as a matter of fact; and our final example of mechanical weathering as well. When animals, and some insects as well, burrow in the ground, they loosen and break apart rocks in the soil. Moles, gophers, prairie dogs, ants, and even earthworms cause this to happen.

This animal's burrow has loosened the soil around it, and broken up rocks inside.